Bilinear magnetoresistance in topological insulators: role of magnetic disorder

TL;DR

This paper investigates how magnetic impurities influence bilinear magnetoresistance in topological insulators, revealing that magnetic disorder generally diminishes BMR magnitude and alters its angular dependence.

Contribution

The study provides a detailed theoretical analysis of magnetic impurity effects on BMR in topological insulators using semiclassical Boltzmann theory.

Findings

Magnetic impurities reduce BMR magnitude.

Magnetic impurities modify the angular dependence of BMR.

Spin-dependent impurity potentials cause additional modulation.

Abstract

Bilinear magnetoresistance is a nonlinear transport phenomenon that scales linearly with the electric and magnetic fields, and appears in nonmagnetic systems with strong spin-orbit coupling, such as topological insulators (TIs). Using the semiclassical Boltzmann theory and generalized relaxation time approximation, we consider in detail the bilinear magnetoresistance in an effective model describing surface states of three-dimensional topological insulators. We show that the presence of magnetic impurities remarkably modifies the BMR signal. In general, scattering on magnetic impurities reduces magnitude of BMR. Apart from this, an additional modulation of the angular dependence of BMR appears when the spin-dependent component of the impurity potential dominates the scalar one.